"The Road to Jerusalem," the first volume of Jan Guillou's new trilogy, involves Swedish politics, familial drama, social oppression, ice fishing, wolf-hunting, political assassination, young sex and the Knights Templar. It's a great book.

The Knights Templar -- a Christian military order closely associated with the Crusades -- have been the go-to guys of historical fiction ever since Sir Walter Scott's "Ivanhoe," but the order has been picking up speed of late in terms of fictional exposure. They can be good guys or bad guys; they're romantic, dramatic and bloody; any insane plot can be attributed to them, either historical or contemporary; and they can't sue for libel. It's to Guillou's credit that he resists the more tempting excesses of these characters.

Somehow, you don't expect a novel about the Crusades to be set in Sweden, but that's just one of the interesting aspects of his book. In the 12th century, of course, it isn't yet Sweden, but the adjoining kingdoms of West Götaland, East Götaland and Svealand. Sverker Sverkersson is king of Eastern Götaland, Erik Jedvardsson is king of Western Götaland, and both of them want all three crowns.

This makes life difficult for Magnus Folkesson, the elder brother of a rich family. Choosing the wrong horse to back could quickly prove fatal, and Magnus, not the brightest torch at the feast, knows his limits. Fortunately, he has a politically astute younger brother and an extremely intelligent wife, who between them have kept Magnus out of trouble, increased his prosperity and given him two sons.

The life Guillou portrays is simple, violent and governed by strict rules. Men own property and kill each other, women bear children (often dying in the process), and marriage is a serious business. Yes, people fall in love, but this really has no bearing on the matter. Marriages are for the preservation of property and the making of political alliances. The landscape is bleak, and so are most people's lives.

Magnus's young son Arn escapes this grim destiny by dying; a fall from a tower window leaves him on the ground, apparently lifeless. But his pious mother prays to the Blessed Virgin while her thralls sneak off and slaughter a sheep to the same end. Someone is evidently listening, for Arn is restored to life. In accordance with his mother's promise to the Virgin, the boy is given to the monks at a nearby abbey, setting in motion an absorbing story of thwarted desire and destiny fulfilled.

The monks are French missionaries, and life inside the cloister is a good deal more civilized than that outside. When the time comes to send Arn back to his family, both he and the world are completely unprepared for each other. Besides his unmanly attention to hygiene and his odd taste for food cooked with spices, Arn has another unsettling skill: He has been taught the arts of swordsmanship and horsemanship by one of the monks -- an ex-Templar doing penance for the crime of usury. His family members are appalled at Arn's flimsy sword and sissy horse -- until they see him in action.

For Arn, the wickedness of the outer world is often confusing, but he does his best to cope. The one thing the monks didn't teach him to deal with, though, was women, and a well-plotted conjunction of politics, business and sex finally sets him on the road to Jerusalem.

It's a beautifully constructed book, with three main stories that play off each other: the contest between two rival kings for the three crowns of the adjoining kingdoms, the rise to power of Magnus's clan and Arn's growth to manhood. Through these three stories twines the tale of the Christian Church and its growing influence.

Despite the intricate plot, "The Road to Jerusalem" is a surprisingly understated book overall. Skillfully written and translated, it's detailed, but sparingly so. At one point, the thrall women make a secret pain-numbing mixture for their mistress, who is suffering in childbirth, noting casually that they usually reserve the medicine for "their own who were about to be whipped, maimed, or gelded." Most historical novelists wouldn't be able to resist telling what was in that mixture, as well as doing a certain amount of maiming and gelding onstage. Guillou leaves it with that one sentence. He has a remarkable grasp of the mind-set of the period and always puts the emphasis where it would be for the people involved at that time, rather than ours. Some readers may find that disorienting, but a capacity for disturbing readers' assumptions is even more a hallmark of good historical fiction than the inclusion of the Knights Templar.

Gabaldon is the author of "An Echo in the Bone," the latest novel in her historical Outlander series, to be released in September.